20 mm. SEMAG Spanish Civil War

[besons]

Hola. Se trata de un lote de cartuchos SEMAG de 20 mm de la Guerra Civil Española. Cualquier información sobre ellos sería muy apreciada.

"Hello. This is a batch of 20 mm SEMAG cartridges from the Spanish Civil War. Any information about them would be greatly appreciated."

Gracias.

 

[besons]

Olvidé mencionar que todos los cartuchos son completamente inertes y las vainas no tienen fulminante. Probablemente eran un recuerdo de guerra de algún soldado.

"I forgot to mention that all the cartridges are completely inert and the casings have no primer. They were probably a war souvenir from some soldier."

 

[Dreamk]

Nice to see that here. One of the rare guns that took my fancy due to its fields of utilization.
The Semag 20mm model 1923 was a development of the World War I Becker 20mm gun. Due to the restrictions of Treaty of Versailles, the patents and designs were transferred in 1919 to the Swiss firm SEMAG (Seebacher Maschinenbau Aktien Gesellschaft). The SEMAG company collapsed in 1924 and its uccession was taken by Oerlikon, though the name Semag stuck till, at least, 1934.
The SEMAG was initially a 20x72RR caliber (SEMAG Typ F) automatic cannon then with the Oerlikon take over in 1924 it was produced with a 20x72RB cartridge case (the Semag/Oerlikon typ FF) then Oerlkon developped its 20x100RR based on it.
The Semag was purcased by Bolivia prior to the Chaco War (1932-1935) (12 guns), of these at least five were captured by the Paraguayans who used them primarily in the A.A. role until captured ammunition was exhausted. Aside from Bolivia and Paraguay, the weapon was employed by the armies of Colombia, Mexico and Peru. The Japanese used a close copy of the Semag, under the deisgnation of Army Type 98 20mm machine cannon.
6 20mm Semag machine guns, and 12.600 cartridges were among teh cargo of the "Mar Cantabrico" seized by the Nationalists in 1937.

Here's the data of the ammunition for the SEMAG 20mm used in the Spanish Civil War in an Anti-Tank role:



It is interesting to see that on the photograph uploaded by besons there are also explosive projectiles, similar to the original Becker ones, that do not appear in the above SCW official documentation.

These are from a French source on teh 1917 Becker ammunition:


The SEMAG Typ F was a close copy of the Becker - here a couple of photos of the original Becker gun: